While attention has been focused on television in the digital migration debate, digital radio has been left out in the cold, despite the advantages it can bring to the listening public. Is it time for SA to adopt digital audio broadcasting technology?

UK telecommunications and broadcasting regulator Ofcom has set 2015 as the year Britain will switch off analogue FM and AM radio broadcasts and migrate completely to digital audio broadcasting (DAB) technology.

The benefits of doing so are clear. Like digital terrestrial television, DAB makes far more efficient use of frequency spectrum than analogue, allowing an order of magnitude more radio stations to be licensed, especially in rural areas.

It’s also much cheaper to maintain (though not to set up) and audio quality is superior, provided broadcasters don’t compress the signal too heavily.

Modern DAB receivers allow listeners to do cool things, like pause or rewind live radio, much like pay-TV subscribers can do with personal video recorders. Think about it: how often have you tuned in to your favourite station and cursed for having caught only the tail end of a news bulletin? With DAB technology, you simply rewind the live broadcast to the beginning of the bulletin.

DAB, which was first deployed by the UK in the mid-1990s, has made significant progress in the past 15 years and is now used in more than 20 countries worldwide.

The original standard, which had a number of technical problems, looks set to be replaced soon with DAB+, which uses an audio compression code — HE-AAC — superior to DAB’s older Mpeg 2. Among other things, DAB+ is more efficient again at using scarce frequency spectrum.

For early adopters of DAB, though, moving to DAB+ is a problem. For one thing, most DAB receivers aren’t able to pick up DAB+ broadcasts. This means people who have already bought digital radio receivers may have to replace them at some point in the future. And DAB radios are more expensive than FM receivers, at least for now. Ofcom has said the UK will migrate to DAB+ only once the vast bulk of digital receivers are able to tune into the broadcasts. That could take years.

Countries like SA, which haven’t yet begun digital radio broadcasts, can leapfrog the early adopters and go straight to DAB+ — or one of the other digital radio broadcasting technologies such as digital radio mondiale.

It must be said that digital broadcast radio has a number of disadvantages over FM and AM broadcasts.

Principal among these is that the cost of digital broadcasting equipment is still much higher than analogue equipment. The up- front costs mean it is often too expensive for smaller broadcasters and community radio stations to broadcast in digital.

This is a problem, given that one of the biggest advantages of digital radio is that it allows greater diversity of content on the airwaves. As digital radio becomes more widespread, though, costs will come down, allowing smaller broadcasters to use it.

Should SA be considering digital radio? After all, the country is in the throes of moving to digital television, so why not switch to digital radio at the same time?

The answer is the country can probably afford to wait before committing itself. FM radio does the job pretty well already, and the cost of the technology is still relatively high.

If we wait a few years, broadcasters may have to fork out a lot less. And the incum- bents will be less likely to be able to hog the available spectrum.

Of course, as bandwidth prices drop and broadband access proliferates, Internet radio could become a disruptive force that eventually undermines traditional broadcast radio, both analogue and digital.